Thread by @NashSevereWx

Forecast is cold rain Saturday. Then Saturday night we see a changeover to wintry precip, then snow into Sunday until around dark.

This is not a universally agreed upon snow event (see below), most data thinks snow is coming so it was time for a Winter Storm Watch.

1/8

"Currently forecast snowfall accumulation amounts generally ranging from 3 to 7 inches across our area . . . potential for locally higher amounts than what is currently being forecasted is certainly possible." -@NWSNashville. A "deformation zone" may form across Middle TN...

2/8

...which is an area of heavy snow, at about 1" per hour. Exactly where that sets up no one really knows, the models keep moving it.

If this deformation zone is a dart, we're one spot on the dartboard.

3/8

So, the play here is to get ready for a big snow. *If* the forecast holds up tonight and tomorrow, then you'll need to put that plan into action. Travel would be bad Saturday night through Sunday into Monday morning.
But all this may change.

4/8

Still think the snow totals could go up, or down. Data doesn't universally agree on the big snow, for example the GFS swings the low too close to us which means mostly rain and little frozen precip ...

5/8

And the HRRR has a much different idea. It drives most of the precip really far south of us. Even tho it only runs until 6 AM Sunday it's low key concerning that we will get cough much, if anything.

6/8

But most models expect a rain to snow changeover Saturday night, and snowing most of the day Sunday. The deformation zone may increase amounts, but a ton of other things may decrease totals.

7/8

Temps aloft may melt falling snow, or change it to sleet. We may see a rain/snow/sleet/freezing rain mix. This would reduce snow totals and introduce more of an icing concern.

Prepare. Stay informed. This may change.

More later.

8/8